It has become apparent, particularly in the field of biological sciences, that there exists a need for radiation sources that can be customized so as to produce a spectrum possessing a set of desired characteristics. This need ranges from illuminating a sample for microscopic evaluation to producing a desired spectrum for the purpose of designed stimulation of cellular activity.
Although there are methods to produce bands of spectra using interference filters, or some variation of spectra separation as used in spectroscopes, these methods exhibit the common deficiency of only permitting contiguous bands of energy to reach the sample. Additionally, these methods are designed to produce discrete bands with sharp frequency cut-offs and eliminate all radiation outside of these bands. Some research or analytical applications require many of these expensive and fragile filters to conduct routine laboratory evaluations.